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Forearm skin blood flow was measured during external pressure loading in normal human subjects using 133Xe washout from intracutaneous injection sites. Pressures ranging between 5 and 150 mmHg were applied through a 3-cm-diameter disc placed over the site of flow determination. The pressure was maintained constant by a servo-controlled loading mechanism. Flow decreased with pressures from 5 to 10 and 30 to 150 mmHg, but remained constant with pressures from 10 to 30 mmHg. Reactive hyperemia occurred following removal of pressures of 90 mmHg or greater, but did not occur following removal of lower pressures. The pressure-flow curve for parasacral skin of paraplegic subjects closely paralleled the pressure-flow curve of normal skin at pressures tested: 5-15 mmHg. These data are interpreted to demonstrate autoregulation of skin blood flow. Autoregulation in parasacral skin of paraplegic subjects suggests a peripheral mechanism. The occurrence of hyperemia at pressures which exceed the ability of skin to autoregulate suggests that both autoregulation and post occlusion hyperemia may have the same mechanism.  相似文献   
13.
The Clausen modification of the peripheral blood buffy coat leukocyte migration test was used to test patients with multiple sclerosis, normal subjects and patients with other neurologic diseases for cell-mediated immunity to commercial measles virus, purified nuclear core material from a human neurotropic strain of measles virus, as well as to commercial preparations of rubella, mumps and parainfluenza HA2. Leukocytes of multiple sclerosis patients showed significantly less mean inhibition of migration in the presence of both measles antigens, mumps and parainfluenza but no difference from controls when incubated with rubella. No correlation could be found between the degree of migration inhibition and concomitant serum anti-measles neutralization antibody titers to the same strain of virus. The use of purified viral antigens might result in more meaningful studies of the status of cellmediated immunity to viral antigens in multiple sclerosis. The relationship of our findings to other studies in this area and to the pathogenesis of multiple sclerosis is discussed.  相似文献   
14.
The effect of exogenous adenine nucleotides on CO2 fixation and oxygen evolution was studied with mesophyll protoplast extracts of the C4 plant Digitaria sanguinalis. Exogenous ATP was found to stimulate the rate of pyruvate and pyruvate+oxalacetate induced CO2 fixation, as well as reverse the inhibition of CO2 fixation of carbonyl cyanide m-chlorophenyl hydrazone and several electron transport inhibitors. The ATP-dependent stimulation of CO2 fixation varied from 40 to 70 mumol CO2 fixed/mg chlorophyll per h, suggesting that ATP was crossing the chloroplast membranes at rates of 80-140 mumol/mg chlorophyll per h, since 2 ATP are required for each CO2 fixed. Fixation of CO2 could also be induced in the dark by exogenous ATP, in which case ADP accumulated outside the chloroplasts...  相似文献   
15.
Fourteen women with amenorrhea-galactorrhea were treated with bromo-ergocryptine. Serum prolactin hPRL, hLH, hFSH, estradiol 17-beta (E2), and progesterone values were determined before and during treatment. No consistent pretreatment hormonal pattern was found. During treatment hPRL levels fell in 13 of 14 patients, and E2 rose in 12 of 14 patients. Levels of hLH became normal, and amounts of hFSH did not change. Galactorrhea lessened in all cases and ceased in 11. Menses resumed in 11 patients and 3 women became pregnant. Cessation of galactorrhea and resumption of menses occurred irrespective of initial hPRL or hLH levels. It is suggested that improvement of galactorrhea and resumption of menses in some patients with normal hPRL values are the result of increased serum E2 levels and may be due to a direct action of bromo-ergocryptine on the ovary. Bromo-ergocryptine may also be effective in treatment of amenorrhea, unassociated with galactorrhea or elevated hPRL levels.  相似文献   
16.
Streptokinase-streptodornase (SK-SD) induced immediate and delayed skin test reactions in a high proportion of patients with disorders in which beta-streptococcal infection may be involved. The P-K test and absorption experiments with antigen or anti-IgE suggested that the immediate reaction was mediated by specific IgE antibody against SK-SD. Furthermore, the ratio of specific IgE antibody against SK-SD to total IgE was roughly calculated to be 20 percent. Finally, the RAST technique was applied to detect specific IgE antibody against SK-SD which showed high radiocounts bound to SK-SD-coupled particles in the sera of nephrotic patients who had a strong immediate reaction against SK-SD and a severe disease state.  相似文献   
17.
A rapid method for the estimation of available lysine in dried milk powder has been developed. Samples were treated with 2,4,6-trinitrobenzene sulfonic acid and then hydrolyzed with 6N HCl. The hydrolysate was purified and subjected to ascending thin layer chromatography to isolate xi-trinitophenyl lysine in pure form. The color was read at 346 nm in a specitrophotometer.  相似文献   
18.
The frequency and severity of CNSLD was studied in workers of an Hungarian firm (Ganz-Mavag) by means of questionnaire. Symptoms of CNSLD can be found more frequently in workers with air pollution than in those without. The symptoms of CNSLD show an age-dependence with regard to frequency and grade of severity, the single symptoms of CNSLD not occurring simultaneously and changing in their proportional frequency.  相似文献   
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Osteoporotic fractures, and in particular, hip fractures result in significant morbidity and mortality. Low bone mass is the main risk factor of enhanced bone fragility, resulting in an increased risk for hip fracture. Bone density of osteoporotic women with and without hip fractures show a considerable overlap. Therefore, other bone-independent factors also play an important role for the development of hip- and other osteoporotic fractures. One other important factor is falling. In 90% of hip fractures falling was involved [10-15], but only 5% or less of these falls resulted in a subsequent fracture. The view that adequate exercise is beneficial for skeletal health of children and for prevention and treatment of osteoporosis in adults is supported primarily by two lines of evidence: longitudinal and cross-sectional trials in children and young adult athletes showing a significant increase of muscle- and bone mass after strenuous (children) or chronic exercise (athletes) as compared to normally active (children) or sedentary control subjects. What are the potential benefits and limits of specific exercise programs with respect to bone mass, prevention of falls and fractures? In this review these questions are discussed and a specific exercise program in osteoporotic patients with fractures is delineated.  相似文献   
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